Apparatus for detecting leaks in blast-furnace-cooling appliances



Nov. 13 1923. IAMAWE J. S. CROWTHER, JR

APPARATUS FOR DETECTING LEAKS IN BLAST FURNACE COOLING APPLIANCES Filed Jan. 31 1921 2 Sheets-Sheet 1 Nov. 13 1923. 11,474,09731 I J. s. CROWTHER, JR

APPARATUS FOR DETECTING LEA-KS IN BLAST FURNACE COOLING APPLIANCES Filed Jan. 31 1921 2 Sheets-Sheet 2 Patented Nov; l3, lQZB.

STATS JOHN S. CROWTI-IER, J11, F TOLEDO, OHIO.

APPARATUS FOR DETECTING LEAKS IN BLAST-FUR-NACE-COOLING APPLIANCES.

Application filed January 31, 1921.

To all whom may concern:

Be it known that 1, JOHN S. CROWTHER, Jr, a citizen of the United States, and a resident of Toledo, county of Lucas,and

5 State of Ohio, have invented a new and useful Improvement in Methods and Apparatus for Detecting Leaks in BlastFurnace- Cooling Appliances, of which the following is a specification, the principle of the inven- 1 tion being herein explained and the best mode in which I have contemplated applying that principle, so as to distinguish it from other inventions.

My invention relates to a method and apparatus for detecting leaking or defective cooling plates, tuyeres and the like in blast furnaces, and has in view the securing of advance information of the failure of such furnace accessories, before the defect has advanced to the stage where it could be detected by any other method. through the collection of air or gas from the cooling element to be tested over a considerable period of time and under conditions which are favorable to the separation of air and gas from the cooling water. More particularly, my invention involves the use of a closed cylindrical reservoir or chamber, provided with appropriate valves, and interposed in the line of fluid circulation of ,the blast furnace cooling appliances whereby the cooling liquid after its circulation adjacent the combustion chamber or hearth may be passed therethrough in contact with a partial vacuum provided therein and minute leakages of furnace gases into such cooling liquid be detected'through analysis of the gas collected within the top of the chamber.

Heretofore, it has been customary to test a cooling unit which was thought to be leaking by. reducing the pressure upon the cooling liquid, which normally is about twenty or twenty-five pounds, to apoint below that prevailing on the inside of the furnace, so that if a crack should be present in such unit, the pressure inside the furnacewould force the gas out through the cooling liquid container and if a torch should be held at the discharge point. result in the indication of a leak through the ignition of such gas.

However, with a test of this character, only leaks of considerable size could be discovered and frequently a bosh plate, tuyere or like cooling device was assumed to be in good condition when minute breaks had already occurred. Should any of the cool- Serial No. 441,196.

ing units crack or be burned through, conditions may arise often dangerous to those about the furnace, and at least involving financial loss through the entrance of considerable quantities of cooling water into the furnace, with the consequent cooling of the furnace and production of metal of an off grade.

With a view of providing means of detecting a leak even of a small degree and obviating the dangers indicated, through the use of the make-shift methods now employed, I have devised the method and provided the apparatus hereinafter fully described and particularly pointed out in the claims.

The annexed drawing and the following description set forth in detail certain apparatus for carrying out the invention, such disclosed means constituting, however, but one of the various structural forms in which the principle of the invention may be used.

In said annexed drawing Figure 1 is a side elevation partly in section, showing my apparatus as applied to the cooling plates of a blast furnace;

Fig. 2 is a side elevation partially in section upon an enlarged scale showing my gas collecting apparatus. a

Fig. 3 is an end view of the device shown in Fig. 2 as seen from the right hand side; and

Fig. 4 is a diagrammatic plan view illustrating the use of a plurality of my gas collecting units in connect-ion with adjacent series of furnace cooling plates.

My invention, as applied to a blast furnace, is illustrated in Fig. 1, wherein is shown a furnace wall lhaving embedded therein a plurality of horizontally placed cooling units or bosh plates 2 having hollow interior portions 3 for the reception of a cooling liquid, usually water, which is circulated through each vertical series of plates by means of appropriate fluid con nections. Thus, there is shown an inlet pipe 4% and an outlet pipe 5 in connection with each of the plates illustrated. The main inlet pipes for the several series may be connected to a. common source of water supply and the outlet pipes of the series usually all discharge into an overflow trough 4-2. In each of the pipes appropriate valves are provided so that the fluid supply may be controlled as desired In order to test the water used within the cooling plates for occluded furnace gases, I interpose in the line of the outlet passageway a gas collecting apparatus 11. A single such apparatus may be used to be connected successively to different cooling units or the gas collecting apparatus, as hereinafter more particularly described in connection with Fig. 4. The number of gas collecting units employed and the arrangement of the connections will be determined by the character of the work to be performed by the furnace, as well as the size of the furnace operation. In addition to fluid connections with the cooling plates, similar connections with the coolers 6 of the tuyeres 7 may be made and any leakage therein detected in a similar manner. As best shown in Fig.2, my gas collecting apparatus comprises a chamber 12 formed by closing each end of a short section of pipe of any desired diameter, though preferably of not less than six inches, by welding to the ends thereof pieces of plate of the appmpriate size. Through the central portion of the top plate 13 an opening 14 is provided, within which is secured a small valve 15 having a nipple 16 at the top thereof. Near the base of the chamber so provided, apertures 17, 18 are located. The aperture 17. intended for the inlet connection with the chamber is upon a slightly higher level than that of the apertime 18 to which the outlet connection is to be applied. WVithin the aperture 17 a pipe section 19 is secured upon the end of which an elbow 20 is attached, the inner section of which extends upwardly a short distance along the central vertical axis of the chamber. An enlarged nozzle section 21 is secured to the upper end of the elbow to permit of the quiet admission of the cooling liquid to the chamber. The outer end of the inlet connection is provided with appropriate means for connecting it with the outlet pipe of the cooling unit, shown in Fig. 2 as the male member 22 of the ground brass union 23 (Fig. 1.)

The outlet connection from the gas collecting chamber, as shown in Fig. 2, comprises a pipe section 24: provided with a valve 25 and elbow connections 26, 27, to permit of attachment to an outlet pipe upon a slightly higher level and which will also serveto retain a certain amount of liquid within the base of the chamberas it is car-- ried about. A bail 28 of substantial construction, shown as a section of pipe of small diameter curved over the top of the chamber and secured at its ends to the sides,

is provided to afford convenient means for carrying the apparatus to various places of use, where a single such apparatus is employed. 1 a

As shown in Fig. 3, a liquid level gauge 31 of'standard construction with a vertical glass tube 32 and valve connections 33, 34, is attached to theside of the chamber. It is preferably of a length sufiicient to indicate the water level within the chamber from a point near the top thereof to slightly below the inlet nozzle.

The method of operating my apparatus is as follows: 7 I r The valve operating in the outlet passageway of the reservoir is closed and a small valve provided with a nipple at the top of the chamber is opened. Water from the cooling appliance to be tested is then ad mitted to the chamber through the inlet pipe until the chamber is tilled as will be indicatedby the over-flow through the nip ple at the top. When this occurs, the top valve of the chamber, and the supply valve in the inlet pipe, are closed, and the lower outlet valve, referred to, is opened. Due to the difference inlevel of the water in the chamber and in the outlet pipe, a partial vacuum is formed in the top of the chamber. Air and gas present in the form of small bubbles in the water flowing through the chamber will separate out at the point of contact with this partial vacuum and collect at the top of the chamber gradually displacing the water therein. The progress of this action can be noted on the gauge glass. \Vhen the level of the water reaches the lower part of the gauge glass at apoint close to the outlet passage-way, a sample of the air and gas mixture is taken through the upper valve. This is done by connecting a gas-sampling tube to the nippleat the top of the reservoir closing the outlet valve and 7 opening the upper valve. The water will then rise in the chamber andforce some of the gas into the sampling-tube. The gas so collected. is analyzed in the laboratory and if characteristic furnace gases (such as car hon-monoxide gas) are found, the cooling plate or tuyere is known to be leaking.

hile my apparatus maybe used as a portable appliance to be connected with various portions of the cool ng system used upon a furnace,l may provide a plurality of such gas collectlng devices connecting with each separate portion of the cooling system. The bosh plates are ordinarily connected in vertical series, the feed line entering the lower plate near the bottom thereof and discharging from the top through a connection entering the next higher plate near the bottom thereof, and like connec-- tions continuing throughout the series, the last dischargepipe opening above an open trough 42, as clearly shown in Fig. 1. Each Cir tuyere, however, receives its water supply directly from the main pressure line and the discharge therefrom passes directly to the overflow trough. All the other coolers and plates of the blast'furnace are customarily connected in series, so that the water is used several times, as above indicated.

As diagrammatically illustrated in Fig. 4, each vertical series of bosh plates 2, the mem bers of which are connected to each other, as shown in Fig. 1, has a connection with a common fluid supply pipe 41, and a connection with a common overflow trough 42, and there is regularly interposed in the line of each outlet connection a gascollecting chamber 11, with its controlling valves 15 and 25. At periodic intervals through the proper manipulation of these valves, as explained above, each such ser'es of cooling devices may be tested. When the test shows a defect present in one or more plates of a particular series, it becomes necessary to separate the plates, connecting the gas collector to each one in turn, and in this way definitely locating the plate or plates that are leaking. Thus, all danger to those connected with the furnace operation, as well as to the product within the furnace, may be avoided by the positive indications given some time in advance of a seriousdefect in the apparatus. Accordingly, the use of this apparatus and method will be found to provide a safety means whereby great losses in the respects noted may be avoided.

I may also make the control of the valves automatic through the use of float or pressure actuated means of conventional design, so that the water level will be changed and the partial vacuum renewed automatically. (was samples may then be taken at any time from the chambers showing the proper water level.

Other modes of applying the principle of my invention may be employed instead of the one explained, change being made as re gards the method or the mechanism herein disclosed, provided the means stated by any of the following claims or the equivalent of such stated means be employed.

1 therefore particularly point out and dis tinctly claim as my invention.

1.. An apparatus for detecting leaks in furnace cooling appliances comprising a cooling liquid container adjacent the furnace combustion chamber, inlet and outlet passage-ways connected therewith, a reservoir, a conduit connected with said outlet passageway and entering the side of said reservoir near its base, an enlarged upwardly turned discharge nozzle on the inner end of said conduit, a valve upon the upper por tion of said reservoir, an outlet passageway connected with said reservoir near its base and a valve in said outlet passageway, said valves being adapted to cause the filling of said reservoir and thereafter to continue the flow of. liquid through the same at a lower level with a partial vacuum formed within the reservoir thereby causing the accumulation of occluded gas within said reservoir where from the leakage of said container may be determined.

2. An apparatus for detecting leaks in furnace cooling appliances comprising a plurality of series of cooling liquid containers adjacent the furnace combustion chamber, a main source of liquid supply, a common liquid outlet passageway, inlet and outlet passageways connecting in parallel each of said containers with said main inlet and outlet passageways, reservoir connected near its base in the line of each of said last named outlet passageways, a valve in the upper portion of said reservoir, and a valve upon the outlet side of said reservoir, said valves being adapted first to cause the filling of any selected reservoir and thereafter to continue the flow of liquid therethrough to the end that minute portions of gas carried by said cooling liquid may be collected in said reser voir and by its character indicate slight leakage in single series of said containers.

3. An apparatus for detecting leaks in furnace cooling appliances comprising a plurality of series of cooling liquid containers adjacent the furnace combustion chamber, a main source of liquid supply, a common liquid outlet passageway, inlet and outlet passageways connectingin parallel each of said containers with said main inlet and outlet passageways, a reservoir connected near its base in the line of each of said last named outlet passageways. a valve in the upper portion of said reservoir, a valve upon the outlet side of said reservoir. said valves being adapted first to cause the filling of any selected reservoir and thereafter to continue the flow of liquid therethrough to the end that minute portions of gas carried by said cooling liquid may be collected in said reservoir and by its character indicate slight leakage in single series of said containers, and elements upon each of said containers whereby separate connection may be mace between any container of the series with its gas collecting reservoir.

4. An apparatus for detecting leaks in furnace cooling appliances comprising a plurality of cooling elements. plurality of gascollecting reservoirs, fluid connections between cooling elements and said reservoirs whereby the cooling liquid is circulated through said reservoirs, and valves automatically operated alternately to fill said reservoirs with liquid and to cause a partial vacuum therein, within which occluded fun nace gases may collect.

Signed by me this 28 day of Jan, 1921.

JOHN s. onowri-inn, JR.

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